A comparison of the fixed combination of latanoprost and timolol with the unfixed combination of brimonidine and timolol in patients with elevated intraocular pressure. A six month, evaluator masked, multicentre study in Europe

Deletion of transcription factor AP-2β from the developing murine trabecular meshwork region leads to progressive glaucomatous changes

Glaucoma is one of the leading causes of irreversible blindness and can result from abnormalities in anterior segment structures required for aqueous humor outflow, including the trabecular meshwork (TM) and Schlemm's canal (SC). Transcription factors such as AP-2β play critical roles in anterior segment development. Here, we show that the Mgp-Cre knock-in (Mgp-Cre.KI) mouse can be used to target the embryonic periocular mesenchyme giving rise to the TM and SC. Fate mapping of male and female mice indicates that AP-2β loss causes a decrease in iridocorneal angle cells derived from Mgp-Cre.KI-expressing populations compared to controls. Moreover, histological analyses revealed peripheral iridocorneal adhesions in AP-2β mutants that were accompanied by a decrease in expression of TM and SC markers, as observed using immunohistochemistry. In addition, rebound tonometry showed significantly higher intraocular pressure (IOP) that was correlated with a progressive significant loss of retinal ganglion cells, reduced retinal thickness, and reduced retinal function, as measured using an electroretinogram, in AP-2β mutants compared with controls, reflecting pathology described in late-stage glaucoma patients. Importantly, elevated IOP in AP-2β mutants was significantly reduced by treatment with latanoprost, a prostaglandin analog that increases unconventional outflow. These findings demonstrate that AP-2β is critical for TM and SC development, and that these mutant mice can serve as a model for understanding and treating progressive human primary angle-closure glaucoma.

Intraocular pressure-lowering effects of commonly used fixed combination drugs with timolol in the management of primary open angle glaucoma

AIM

To evaluate intraocular pressure (IOP)-lowering effect and ocular tolerability of brimonidine/timolol, dorzolamide/timolol and latanoprost/timolol fixed combination therapies in the management of primary open angle glaucoma.

METHODS

Each drug was administered for two months, after which a circadian tonometric curve was recorded using a Goldmann applanation tonometer. Ocular discomfort (conjunctival hyperemia, burning or stinging, foreign body sensation, itching, ocular pain) of each eye was assessed by the subject on a standardized ocular discomfort scale.

RESULTS

Among the three study groups, there were no significant differences in the mean baseline IOP measurements, mean 2(nd) mo IOP measurements, and mean (%) change of IOPs from baseline. Among the three study groups, there were no significant differences in the mean IOP measurements obtained at circadian tonometric curves at baseline and at two months controls. In sum brimonidine/timolol, dorzolamide/timolol and latanoprost/timolol fixed combination therapies showed similar effects on IOP levels.

CONCLUSION

Brimonidine/timolol, dorzolamide/timolol and latanoprost/timolol fixed combination therapies showed similar lowering efficaties on IOP levels whereas there was no any difference between each other.

Long-term medical management of primary open-angle glaucoma and ocular hypertension in the UK: optimizing cost-effectiveness and clinic resources by minimizing therapy switches

PURPOSE

The objective was to assess the long-term economic consequences of the medical management of glaucoma in the UK.

METHODS

The economic evaluation was conducted using the results from a 10-year Markov model based around 3 key triggers for a switch in medical therapy for glaucoma, namely: lack of tolerance (using hyperemia as a proxy); intraocular pressure (IOP) not meeting treatment benchmark; and glaucoma progression. Clinical data from a comprehensive systematic literature review and meta-analysis were used. Direct costs associated with glaucoma treatment are considered (at 2008/9 prices) from the perspective of the UK NHS as payer (outpatient/secondary care setting). Using this model, the economic consequences of 3 prostaglandin-based treatment sequences were compared.

RESULTS

Drug acquisition costs account for around 8% to 13% of the total cost of glaucoma and, if ophthalmologist visits are included, amount to approximately £0.80 to £0.90 per day of medical therapy. The total long-term costs of all prostaglandin strategies are similar because of a shift in resources: increased drug costs are offset by fewer clinic visits to instigate treatment switches, and by avoiding surgery or costs associated with managing low vision. Under the latanoprost-based strategy, patients would have longer intervals between the need to switch therapies, which is largely due to a reduction in hyperemia, seen as a proxy for tolerance. This leads to a delay in glaucoma progression of 12 to 13 months. For every 1000 clinic appointments, 719 patients can be managed for 1 year with a latanoprost-based strategy compared with 586 or 568 with a bimatoprost or travoprost-based strategy.

CONCLUSIONS

Drug acquisition costs are not a key driver of the total cost of glaucoma management and the cost of medical therapy is offset by avoiding the cost of managing low vision. Economic models of glaucoma should include the long-term consequences of treatment as these will affect cost-effectiveness. This analysis supports the hypothesis that the economic and clinical benefits can be optimized by minimizing therapy switches.

Intraocular pressure-lowering effects of commonly used fixed-combination drugs with timolol: a systematic review and meta-analysis

Background

The first goal of medical therapy in glaucoma is to reduce intraocular pressure (IOP), and the fixed-combination medications are needed to achieve sufficiently low target IOP. The aim of this systematic review and meta-analysis is to evaluate IOP-lowering effect of the commonly used fixed-combination drugs containing 0.5% timolol.

Methods

Pertinent publications were identified through systematic searches. Over 85% of the patients had to be diagnosed with primary open-angle glaucoma (POAG) or ocular hypertension (OHT). Forty-one randomized clinical trials were included in the meta-analysis. The main efficacy measures were the absolute and relative values of mean diurnal IOP reduction, and the highest and lowest IOP reductions on the diurnal IOP curve. The pooled 1- to 3-month IOP-lowering effects after a medicine-free washout period was calculated by performing meta-analysis using the random effects model, and relative treatment effects among different fixed combinations were assessed using a mixed-effects meta-regression model.

Results

The relative reductions for mean diurnal IOP were 34.9% for travoprost/timolol, 34.3% for bimatoprost/timolol, 33.9% for latanoprost/timolol, 32.7% for brinzolamide/timolol, 29.9% for dorzolamide/timolol, and 28.1% for brimonidine/timolol. For the highest IOP decrease, relative reductions ranged from 31.3% for dorzolamide/timolol to 35.5% for travoprost/timolol; for the lowest IOP decrease, those varied from 25.9% for dorzolamide/timolol to 33.1% for bimatoprost/timolol. Both latanoprost/timolol and travoprost/timolol were more effective in lowering mean diurnal IOP than brimonidine/timolol (WMD: 5.9 and 7.0) and dorzolamide/timolol (WMD: 3.8 and 3.3).

Conclusions

All six commonly used fixed-combination drugs containing timolol can effectively lower IOP in patients with POAG and OHT, and both latanoprost/timolol and travoprost/timolol might achieve better IOP-lowering effects among the six fixed-combination agents.

Comparison of timolol 0.5% + brimonidine 0.2% + dorzolamide 2% versus timolol 0.5% + brimonidine 0.2% in a Mexican population with primary open-angle glaucoma or ocular hypertension

Background

The purpose of this study was to evaluate the efficacy and safety of two fixed combinations, ie, timolol 0.5% + brimonidine 0.2% + dorzolamide 2% (TBD) versus timolol 0.5% + brimonidine 0.2% (TB) in patients with primary open-angle glaucoma or ocular hypertension.

Methods

We performed a 3-month, randomized, double-blind study in patients with primary open-angle glaucoma or ocular hypertension and an intraocular pressure of 21–30 mmHg. Patients were randomly assigned to receive one drop of TBD or TB twice a day. The primary efficacy endpoint was change in intraocular pressure after 3 months of treatment. Safety measures were assessed by the presence of adverse events.

Results

Mean baseline intraocular pressure was similar at 8 am and 4 pm in the treatment groups (TBD 22.3 ± 0.9 mmHg, TB 22.4 ± 1.8 mmHg, P = 0.558; TBD 19.02 ± 1.3, TB 19.08 ± 1.2, P = 0.536, respectively). At the end of the study, the mean intraocular pressure was significantly lower in the TBD group at both 8 am (16.19 ± 2.0 mmHg versus 18.35 ± 1.4 mmHg, P = 0.000) and 4 pm (14.74 ± 2.4 mmHg versus 16.77 ± 1.4 mmHg, P = 0.000).

Conclusion

Fixed-combination TBD was more effective than fixed-combination TB for reducing IOP in patients with primary open-angle glaucoma.

Interventions for age-related visual problems in patients with stroke

BACKGROUND

The prevalence of eye problems increases with age and, consequently, so does the level of visual impairment. As the incidence of stroke also increases with age, a significant proportion of stroke patients will have age-related visual problems. It is possible that the effect of interventions for age-related visual problems may differ in the population of stroke patients compared to the wider population of older people. The interaction between the problems arising directly from stroke and those arising directly from age-related visual problems will be complex. Interventions for age-related visual problems may also be affected by the presence of other stroke-related co-morbidities. Consequently, the nature and outcome of interventions for age-related visual problems may be different in patients with stroke.

OBJECTIVES

The aim of this review is to determine if interventions for age-related visual problems improve functional ability following stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (March 2011), the Cochrane Eyes and Vision Group Trials Register (December 2009) and nine electronic bibliographic databases including: the Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 1), MEDLINE (1950 to February 2011), EMBASE (1980 to February 2011), CINAHL (1982 to February 2011), AMED (1985 to February 2011) and PsycINFO (1967 to February 2011). We also searched reference lists and trials registers, handsearched journals and conference proceedings, and contacted experts.

SELECTION CRITERIA

Randomised trials in adults after stroke, where the intervention is specifically targeted at assessing, treating or correcting age-related visual problems, or improving the ability of the patient to cope with visual impairment. Primary outcome was functional ability in activities of daily living and secondary outcomes included functional ability in extended activities of daily living, visual acuity, visual field, visual function, balance, falls, depression and anxiety, discharge destination/residence after stroke, quality of life and social isolation, adverse events and death.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened abstracts and planned to extract data and appraise trials. We planned that assessment of methodological quality would be undertaken for allocation concealment, blinding of outcome assessor, method of dealing with missing data and other potential sources of bias.

MAIN RESULTS

We considered 7357 titles, 460 abstracts and 85 full papers. We identified no studies for inclusion in this review.

AUTHORS' CONCLUSIONS

There are no implications for practice arising from this review. Evidence relating to the management of patients (from the general population) with age-related visual problems is available from other Cochrane reviews and is likely to be the best evidence available for making treatment decisions about individual patients. Subgroup analyses within these reviews to explore the effect of interventions for age-related visual problems in patients with stroke are recommended. We recommend that the objectives and selection criteria for this Cochrane review are amended and clarified prior to any future updates.

The management of glaucoma and intraocular hypertension: current approaches and recent advances

In the last decade, numerous novel ocular hypotensive agents have been introduced for the control of intraocular pressure (IOP). Clinicians now have more options than ever in the selection of medical therapy for the treatment of glaucoma and ocular hypertension. When selecting an ocular hypotensive medication for their patients, clinicians should consider not only the IOP-lowering efficacy of an agent, but also the ability of the drug to allow patients to achieve target levels of IOP that are low enough to stop the progression of glaucomatous damage. Other considerations should include how well the drug controls diurnal IOP, the likelihood of serious adverse events, the versatility of the medication for use as an adjunctive agent, as well as other potential attributes (ie, neuroprotection).

Mixed treatment comparison of repeated measurements of a continuous endpoint: an example using topical treatments for primary open-angle glaucoma and ocular hypertension

Mixed treatment comparison (MTC) meta-analyses estimate relative treatment effects from networks of evidence while preserving randomisation. We extend the MTC framework to allow for repeated measurements of a continuous endpoint that varies over time. We used, as a case study, a systematic review and meta-analysis of intraocular pressure (IOP) measurements from randomised controlled trials evaluating topical ocular hypotensives in primary open-angle glaucoma or ocular hypertension because IOP varies over the day and over the treatment course, and repeated measurements are frequently reported. We adopted models for conducting MTC in WinBUGS (The BUGS Project, Cambridge, UK) to allow for repeated IOP measurements and to impute missing standard deviations of the raw data using the predictive distribution from observations with standard deviations. A flexible model with an unconstrained baseline for IOP variations over time and time-invariant random treatment effects fitted the data well. We also adopted repeated measures models to allow for class effects; assuming treatment effects to be exchangeable within classes slightly improved model fit but could bias estimated treatment effects if exchangeability assumptions were not valid. We enabled all timepoints to be included in the analysis, allowing for repeated measures to increase precision around treatment effects and avoid bias associated with selecting timepoints for meta-analysis.The methods we developed for modelling repeated measures and allowing for missing data may be adapted for use in other MTC meta-analyses.

Fixed combination of topical brimonidine 0.2% and timolol 0.5% for glaucoma and uncontrolled intraocular pressure

Lowering IOP is the most readily modifiable risk factor to delay the development and progression of glaucoma (POAG). The fixed combination of brimonidine tartrate 0.2% and timolol maleate 0.5% (FCBT) combines a highly selective α2-adrenergic agonist (brimonidine) with a non-selective β-blocker (timolol). FCBT reduces aqueous production and enhances uveoscleral outflow. Concomitant brimonidine and timolol have additive effects on reducing intraocular pressure (IOP). Multi-center randomized control trials have documented superiority of FCBT twice daily on IOP control compared with monotherapy with the individual components, and equal efficacy compared with concomitant therapy. IOP reduction with FCBT versus fixed combination dorzolamide 2% and timolol 0.5% (FCDT) was similar in a small study. Other studies (n > 293) evaluating concomitant brimonidine and timolol have shown that it is not inferior to FCDT. However, concomitant brimonidine and timolol administered twice daily was significantly less efficacious in IOP reduction than fixed combination latanoprost 0.005% and timolol 0.5% (FCLT). There are no published studies comparing FCBT with FCLT. The side effect profile for FCBT reflects that of its individual components. FCBT was generally well tolerated, with less ocular side effects than brimondine alone, but more than timolol alone. Documented systemic effects were few, although this could be confounded by selection bias. FCBT is a safe and effective IOP lowering agent for POAG and ocular hypertension.

Clinical utility and differential effects of prostaglandin analogs in the management of raised intraocular pressure and ocular hypertension

Prostaglandin analogs (PGA) are powerful topical ocular hypotensive agents available for the treatment of elevated intraocular pressure (IOP). Latanoprost 0.005% and travoprost 0.004% are prodrugs and analogs of prostaglandin F2α. Bimatoprost 0.03% is regarded as a prostamide, and debate continues as to whether it is a prodrug. The free acids of all 3 PGAs reduce IOP by enhancing uveoscleral and trabecular outflow via direct effects on ciliary muscle relaxation and remodeling of extracellular matrix. The vast majority of clinical trials demonstrate IOP-lowering superiority of latanoprost, bimatoprost and travoprost compared with timolol 0.5%, brimonidine 0.2%, or dorzolamide 2% monotherapy. Bimatoprost appears to be more efficacious in IOP-lowering compared with latanoprost, with weighted mean difference in IOP reduction documented in one meta-analysis of 2.59% to 5.60% from 1- to 6-months study duration. PGAs reduce IOP further when used as adjunctive therapy. Fixed combinations of latanoprost, bimatoprost or travoprost formulated with timolol 0.5% and administered once daily are superior to monotherapy of its constituent parts. PGA have near absence of systemic side effects, although do have other commonly encountered ocular adverse effects. The adverse effects of PGA, and also those found more frequently with bimatoprost use include ocular hyperemia, eyelash growth, and peri-ocular pigmentary changes. Iris pigmentary change is unique to PGA treatment. Once daily administration and near absence of systemic side effects enhances tolerance and compliance. PGAs are often prescribed as first-line treatment for ocular hypertension and open-angle glaucoma.

Mixed treatment comparison and meta-regression of the efficacy and safety of prostaglandin analogues and comparators for primary open-angle glaucoma and ocular hypertension

OBJECTIVES

Primary open-angle glaucoma (POAG) is a chronic condition characterised by optic neuropathy and vision loss. Elevated intraocular pressure (IOP) can damage the optic nerve and is a risk factor for glaucoma, thus treatment usually comprises topical hypotensives. This analysis aims to address methodological issues associated with the synthesis of glaucoma clinical trial data, given variations in study methodology and IOP measurement.

METHODS

Meta-regression was used to estimate how IOP varies over time for patients receiving treatment. Relative treatment effects were assessed using a random-effects mixed treatment comparison (MTC) in order to preserve randomisation and avoid selection bias. To produce clinically meaningful outputs, these analyses were combined to obtain the mean on-treatment IOP and the proportion of patients achieving different IOP targets at different time points. A further MTC estimated the probability of hyperaemia events.

RESULTS

The analysis showed that after 3 months' treatment, between 58 and 83% of patients will have a > or =20% reduction in IOP and 70-93% of patients will have an absolute IOP <20 mmHg. Latanoprost and bimatoprost were found to produce significantly lower on-treatment IOP compared with timolol (p < 0.05); the difference between latanoprost and bimatoprost was not significant. Travoprost produced a lower mean IOP compared with timolol (not significant). Latanoprost-timolol was found to produce significantly lower IOP than latanoprost alone or beta-blockers. The probability of hyperaemia-type events varied between treatments from 14.8 to 63.03%. Latanoprost had significantly lower odds of hyperaemia than travoprost, bimatoprost, travoprost-timolol, or bimatoprost-timolol.

CONCLUSION

This analysis suggests that latanoprost and bimatoprost produce a statistically significant reduction in IOP compared with timolol, but are associated with a higher risk of hyperaemia. Out of all the prostaglandins, latanoprost may achieve a good balance between tolerability and IOP efficacy. As with all forms of meta-analysis, the results are based on the assumption that the studies and intervention groupings are sufficiently similar to be compared.

Efficacy and safety of fixed combinations of latanoprost/timolol and dorzolamide/timolol in open-angle glaucoma or ocular hypertension

AIMS

To compare intraocular pressure (IOP) reductions with fixed-combination (FC) latanoprost/timolol once daily in the evening vsFC dorzolamide/timolol twice daily.

METHODS

This evaluator-masked, multicentre, controlled clinical trial randomized subjects with primary open-angle glaucoma or ocular hypertension with IOP insufficiently responsive to beta-blocker therapy (screening IOP>21 and <37 mm Hg) to FC latanoprost-timolol (N=135) or FC dorzolamide/timolol (N=135). At screening, baseline, and after 4 and 12 weeks of therapy, IOP was measured three times at 0800, 1200, and 1600 hours. Adverse events were recorded at each visit. The primary efficacy end point was whether either FC could be shown to be inferior to the other with respect to change in mean daytime IOP from baseline to week 12.

RESULTS

Mean daytime IOP levels were similar at baseline. Mean reductions in daytime IOP from baseline to week 12 were -9.7 mm Hg for FC latanoprost-timolol and -9.5 mm Hg for FC dorzolamide/timolol. The difference between FC latanoprost/timolol-FC dorzolamide-timolol was -0.2 mm Hg (95% confidence interval (CI), -0.8 to -0.4 mm Hg). The upper bound of the 95% CI was <1.5 mm Hg, indicating that neither FC is inferior to the other. However, a significantly greater percentage of subjects treated with FC latanoprost/timolol achieved IOP levels<or=16 and <or=15 mm Hg (P<or=0.01). Both treatments were well tolerated.

CONCLUSIONS

When beta-blocker therapy is inadequate, either FC may achieve the desired IOP level, but FC latanoprost/timolol more often achieves a pressure of <or=16 mm Hg. Both FCs were well tolerated.

Interventions for improving adherence to ocular hypotensive therapy

BACKGROUND

Poor adherence to therapy is a significant healthcare issue, particularly in patients with chronic disease such as open angle glaucoma. Treatment failure may necessitate unwarranted changes of medications, increased healthcare expenditure and risk to the patient if surgical intervention is required. Simplifying eye drop regimes, providing adequate information and ongoing support according to patient need, may have a positive effect on improving adherence.

OBJECTIVES

To summarise the effects of interventions for improving adherence to ocular hypotensive therapy in people with ocular hypertension (OHT) or glaucoma.

SEARCH STRATEGY

We searched CENTRAL, MEDLINE, EMBASE, CINAHL, PsycINFO, Web of Science, ZETOC and OpenSIGLE. In addition, we searched research registers of ongoing studies. We contacted pharmaceutical manufacturers to request unpublished data and searched conference proceedings for the Association for Research in Vision and Ophthalmology (ARVO), and the Annual Congress for the Royal College of Ophthalmologists (RCO). There were no language or date restrictions in the search for trials. The electronic databases were last searched on 15 January 2009.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi RCTs that compared interventions to improve adherence to ocular hypotensive therapy for patients with OHT or glaucoma.

DATA COLLECTION AND ANALYSIS

At least two authors independently assessed the search results for eligibility and extracted data for included trials onto specifically designed forms. We calculated the mean difference for continuous data and relative risks for dichotomous data. Where appropriate, we pooled data using a fixed-effect model.

MAIN RESULTS

Eight trials met the inclusion criteria. There was considerable heterogeneity of interventions and reported outcome measures and therefore, meta-analysis was limited to two studies. Overall, studies were not of high quality due to small sample sizes, missing data and short term follow-up. Three of five drug comparison studies provided evidence that reducing the frequency of drops can improve adherence. However, the study that compared the least frequent regime with one of the most complicated, showed no difference in reported adherence. A small study of thirteen patients found a reminder device beneficial to adherence levels yet only one of two studies involving education and individualised care planning was found to be successful.

AUTHORS' CONCLUSIONS

Interventions involving simplified dosing regimes, reminder devices, education and individualised care planning, did show improvements in adherence rates. However, due to inadequate methodological quality and heterogeneity of study design we are unable to advocate any particular interventions at this time.

Tolerability, quality of life, and persistency of use in patients with glaucoma who are switched to the fixed combination of latanoprost and timolol

This study was undertaken to assess tolerability, quality of life, and persistency of use and to monitor changes in intraocular pressure (IOP) during the first 6 mo after a switch to fixed combination latanoprost/timolol. In Germany, 271 general ophthalmology practices enrolled patients who were switched from previous ocular hypotensive therapies to latanoprost/timolol for medical reasons. Usual care routines were followed, and IOP was measured at baseline and approximately 6 mo later. Adverse events were recorded throughout. Immediately before switching and at follow-up, patients completed a 29-item quality-of-life questionnaire. Of 1052 patients who met analysis criteria, 748 (71%) switched from combination therapy and 304 (29%) from monotherapy. An insufficient IOP reduction with the previous therapy was a reason for switching in 71% of patients; the desire to simplify to once-daily administration was cited in 66%. Ocular adverse events were reported in 19 patients after the switch, and 97% remained on therapy throughout the follow%up period. After switching, patients were less likely to forget to instill their eyedrops or to feel that their drops had adverse effects; they found it easier to include eyedrop administration in their routine; they were more satisfied with the frequency of instillation; and they were more likely to want to continue with the drops. Across all previous therapies, mean IOP decreased from 20.6+/-3.7 mm Hg to 17.2+/-2.8 mm Hg after the switch (P<.001)-a 14.8% difference. Fixed combination latanoprost/timolol is well tolerated and effective in patients who are switched from other monotherapies or combination therapies for medical reasons. Such a switch may be associated with improved quality of life.

Meta-analysis of randomised controlled trials comparing latanoprost with brimonidine in the treatment of open-angle glaucoma, ocular hypertension or normal-tension glaucoma

AIM

To compare the efficacy and tolerability of latanoprost versus brimonidine in the treatment of open-angle glaucoma, ocular hypertension or normal-tension glaucoma.

METHOD

Systematic review of randomised controlled trials comparing latanoprost and brimondine, identified by searches including Medline, Embase and Cochrane Controlled Trials Register. Two reviewers independently assessed trials for eligibility and quality and extracted data. Data were synthesised (random effects model) and expressed as the absolute mean intraocular pressure (IOP) reduction difference from baseline to end point for efficacy and relative risk for adverse events. Subgroup analysis and regression were used to explore heterogeneity according to patient characteristics, trial design and quality.

RESULTS

15 publications reporting on 14 trials (1784 participants) were included for meta-analysis. IOP reduction favoured latanoprost (weighted mean difference (WMD) = 1.10 mm Hg (95% confidence interval (CI) 0.57 to 1.63)). Significant heterogeneity was present (chi(2)(13) = 38.29, p = 0.001, I(2) = 66.0%). Subgroup analysis showed greater WMD for studies where data were analysed from end points >6 months duration, cross-over design, open-angle glaucoma or ocular hypertension and monotherapy. Multiple regression showed no significant association of WMD with trial duration (t(9) = 1.92, p = 0.09), trial design (t(9) = 1.79, p = 0.11), trial quality (t(9) = -0.46, p = 0.66), or monotherapy or adjunctive therapy (t(9) = -2.14, p = 0.06). Fatigue was less commonly associated with latanoprost (RR = 0.27, 95% CI 0.08 to 0.88). Publication bias was not evident on visual inspection of a funnel plot.

CONCLUSION

Latanoprost is more effective than brimonidine as monotherapy in lowering IOP. Brimonidine is associated with a higher rate of fatigue.

A 12-week, randomized, double-masked, multicenter study of the fixed combination of latanoprost and timolol in the evening versus the individual components

PURPOSE

To compare the efficacy and tolerability of fixed-combination latanoprost and timolol applied in the evening with the concomitant use of the individual components.

DESIGN

Twelve-week, randomized, double-masked, multicenter study.

PARTICIPANTS

Five hundred seventeen randomized patients with ocular hypertension; open-angle, pigmentary, or exfoliation glaucoma; and baseline (after washout) intraocular pressure (IOP) levels between 23 and 33 mmHg.

METHODS

Patients received either the fixed combination of latanoprost and timolol once daily in the evening and a placebo in the morning and evening or the unfixed combination of latanoprost once daily in the evening and timolol in the morning and evening. Study visits were at weeks 2, 6, and 12.

MAIN OUTCOME MEASURES

The primary efficacy end point was mean change from baseline to week 12 in diurnal IOP (mean IOPs of 8 am, 12 pm, and 4 pm). The fixed combination was considered noninferior to the unfixed combination if the upper limit of the 95% confidence interval (CI) of the difference was <1.5 mmHg (analysis of covariance). Adverse events were recorded at each visit.

RESULTS

In all, 502 patients were included in intent-to-treat analyses (fixed combination, n = 255; unfixed combination, n = 247). For the fixed- and unfixed-combination groups, mean baseline diurnal IOP levels were 25.4 mmHg and 25.2 mmHg, respectively, and mean diurnal IOP reductions were 8.7 mmHg and 9.0 mmHg (between-treatment difference, 0.3 mmHg; 95% CI, -0.1 to 0.7 mmHg; P = 0.15). Both treatments were well tolerated.

CONCLUSIONS

The fixed combination of latanoprost and timolol administered once daily in the evening is not inferior to the unfixed combination of latanoprost once daily in the evening and timolol twice daily. The fixed combination provides an effective and well-tolerated alternative to multiple instillations.

Cost considerations of the new fixed combinations for glaucoma medical therapy

OBJECTIVE

To compare the costs of the new fixed combinations for glaucoma medical therapy.

METHODS

The studied drugs were: Cosopt (5-mL bottle), Combigan (5-mL bottle) and Xalacom (2.5-mL bottle). Five bottles of each drug were obtained from pharmacies, and the medications lot numbers were recorded. To calculate the drop volume, 10 drops and 1 mL of each bottle were weighed with a digital precision scale. Drop volume was calculated by the relation between volume and weight. The cost of each bottle of medication was determined from the average retail price in Canada. The prices were obtained in Canadian dollars (dollars).

RESULTS

The drops of Cosopt (39.60 +/- 0.45 microL) were considerably larger than the drops of Combigan (33.75 +/- 0.60 microL) and Xalacom (30.87 +/- 0.37 microL). The average number of drops per millilitre varied from 25.25 +/- 0.29 (Cosopt) to 32.40 +/- 0.39 microL (Xalacom). Combigan presented the lowest daily cost (dollars 0.87 +/- 0.02) followed by Xalacom (dollars 1.09 +/- 0.01) and Cosopt (dollars 1.22 +/- 0.01). The average cost by year varied from dollars 316.75 +/- 5.59 (Combigan) to dollars 445.96 +/- 5.16 (Cosopt), with a total difference of dollars 129.21 per year of treatment.

CONCLUSIONS

There was a statistically significant difference in average drop size and cost among the three studied drugs. Combigan presented the lowest daily cost followed by Xalacom and Cosopt.